As known, when the power supply to a high-speed gyroscope rotor is interrupted, either intentionally or accidentally, the rotor will slow down because of resistive and frictional forces. If the rotor is not perpendicular to the shaft of the outer gimbal assembly, the inner gimbal assembly may pivot with respect to the outer gimbal assembly, to engage a stop thereon, and to cause the whole outer gimbal assembly to rotate with respect to the frame. This may cause damage to the gyroscope, and therefore a number of centrifugal brake arrangements have been devised for limiting the rotational speed of the outer gimbal assembly with respect to the frame. U.S. Pat. No. 3,363,473 illustrates one example of a known centrifugal brake for this purpose, and our patent specification No. 61077 illustrates another example. As a rule, however, the known centrifugal brakes are capable of limiting the rotational speed of the outer gimbal assembly only to about 350 RPM.
An object of the present invention is to provide a new centrifugal brake for limiting the rotational speed of a rotatable body with respect to a reference body. A more particular object of the invention is to provide a novel gyroscope having an improved centrifugal brake which is capable of limiting the rotational speed of the outer gimbal assembly with respect to the gyroscope frame to a lower speed than the previously-mentioned centrifugal brakes.